The construction of houses typically involves the laying of a foundation, the construction of a steel or timber stud frame, layering of insulation material, laying a brick veneer or other outer wall treatment to form the external wall and the fixing of plasterboard sheeting on the frame to form the internal wall. Plasters, masonry tradesman and painters are required to finish the walls. As different tradesman perform different jobs the construction of walls for a house is often slow and labour intensive.
A number of prefabricated walls have been developed to address this problem. In U.S. Pat. No. 4,567,699 there is described a prefabricated panel and building system where each panel is formed with at least one load bearing tube and slots in the upper and lower end walls to receive a T-shaped bearer. The load bearing tube is longer than the length of the panel in order to transfer load forces. A composite wall panel is described in U.S. Pat. No. 5,822,940 where the panel comprises a polymer foam body with a light metal gauge hollow stud extending the length of the body. The panel is the width of the stud and the side wall of the stud forms a wall surface of the body. The panel fits within floor and ceiling track sections to fix the panel in position. Another structural wall panel is described in U.S. Pat. No. 6,481,172. This panel has a foam inner core sandwiched between plastic paper sheets. The internal surface can also have a further gypsum or cement composite layer to provide a finished surface. Each panel is made with compression struts to accommodate axial loading on the panel. The side end walls are recessed in order to overlap and connect to a vertical wooden stud. A further prefabricated panel is described in US 2007/0163197. The panel described in US 2007/0163197 has a plurality of vertically disposed channel-shaped metal studs equidistantly disposed between a bottom and top plate and rigid foam inserts between the studs. There are apertures in the foam inserts to provide for electrical and plumbing connections. Each panel has recessed side end walls and adjacent panels are joined by the positioning of a rigid foam spline between adjacent side end walls so that the spline fits within the opposing recesses and causes the adjacent panels to abut.
Each of the described prefabricated panels includes one or more studs within the panel during manufacture. This feature adds to the complexity of their manufacture and presents problems during transport and on-site storage. Furthermore the structural integrity of the prefabricated panel is largely fixed during manufacture and additional studs cannot be added or excess studs removed when desired.